 Hola woodworkers Paul Croson here small workshop guy today's video is about building this cross-cut sled It is designed to use the match fit dovetail clamps. That's not so unique, but I think it's a good idea But also I have these holes three-quarter inch holes a lot of them in the sled and I'll be explaining the science Behind those that make this a very unique sled tune if you haven't subscribed to my channel I'd appreciate it if you do so and I'd love it if you'd leave some comments and Some likes and maybe even share this puppy with some of your woodworking friends You'll notice a brand new patreon link in the description if you hurry you can be one of my first patreon supporters That's funny. There's probably no hurry at all My goal in this sled was to have a fairly large one But yet a very light one so the first thing I did was measure or weigh the components so that I would know what I was starting with so I took three-quarter inch birch plywood and Started laminating together the front and back fences and then using my saw stallions. I Started cutting out some of the unneeded parts of the sled Which are the corners they're really not needed to support any work. He got the middle of the sled to do that I started by off-camera putting in two dovetail slots at an angle and what I'm demonstrating here as These match fit clamps you can take off a little holding piece on the top and turn the clamp around and Then you can have the hold down piece be further than your slot All right, I have some more slots to put in there so I'm putting on these the bench saddles from Lee Valley hardware and That allows me to put a temporary sacrificial fence up on top of my workbench So I can do some cutting and stuff without damaging my samurai carpenter workbench and this is one of my Track guides that I built using the match fit dovetail clamp system And so I'm using that to do some more slots So here you can see I'm already using the match fit Clamps in the grooves to hold down my track and then using my router to cut some more dovetail right Slots now I'm going to put some holes in this I'll explain at the end of the video why and To do the holes I used a three-quarter inch wood owl auger bit And the secret here is not to press down hard and it'll stop by itself before it tears out in the bottom. I Flip the sled over and I use a three-quarter inch spade bit to finish up those holes Then a little sanding to get everything smooth on the top from all of that drilling and Flip it over and did the other side as well And then use a little sandpaper on the fingertip to clean out the inside of those holes Moving the clamps around you'll find it's very helpful to have a little hammer to tap them. They move much easier that way I'm on the table saw doing an initial cut on the back and front pincers to cut them down to two and a half inches tall in order to remove excess wood and lighten up the total load So we'll see a 10 glue first in order to put down the far fence and Then When that's all set turn it over do some countersink holes and drill some screws in there to hold that Securely the alignment of that fence is not important at all So now we're going to use the William Ng five-cut method. Unfortunately, we're going to use it several times in order to get the Critical fence aligned. That's the one that we want to be 90 degrees to the saw blade and the table saw fence We're going to start by anchoring one corner of the fence to the sled Need to use countersink drill bits so that the screws Do not protrude from the bottom. We temporarily align the back fence using a t-square and then we put in a Screw we clamped it first so it wouldn't move once that's imposition we cut all the way through the sled Now it's time for the William Ng five-cut method to measure how precisely the fence has been set I Write on one side of the board one and five and then I write two three and four on the other sides And then I cut them in that order When I do the fifth cut I make a little bit larger so that I can measure things I make a note of what was atop and what was the bottom I use the calipers and I do a precise measurement I compare those measurements subtract the difference Divide that by four divide that by the length of the fifth cut and then Multiply that times the distance from the one end of the fence to the other Did you follow all that? We'll put a link to the William Ng video so that you can see exactly how this is all done I clamp a piece of wood that has a point on it to the existing fence And then I use a feeler gauge to adjust the fence in this case back toward the garage door By the distance I think I need and then I secure it with a new screw and then I do another five-cut method did the same measuring still wasn't there so Calculated how much I needed to move it again put that pointed stick there Move my fence back by that amount re-screwed it and now doing my final cut. I Know that a little quick, but again, what's the William Ng famous video? so here's my hopefully final cut So I didn't show you all the cuts, but I did the five cuts did my measuring here. I Got my fingers crossed hoping things are gonna work out and Let me take you through the math a little bit more slowly that's involved When I get to that section admiring my result So here's again a summary of how it works. I take that cut-off board That I had marked the top and the bottom and I put the measurement for the top down there I put the measurement for the bottom there. I subtract the difference and Then I divide that by four which does I did four sides and Get a measurement then I divide that by the length of this piece of wood to get my basically my error rate per inch and I got a result of point 000025 and so If I multiply that times 10 inches that would be an error of 2000s over a 10 inch and that's good enough for the kind of work that I do so Happy with the way that is now. I'm gonna just secure it with some screws Obviously countersink so that they don't scrape on your tabletop and that completes my cross-cut slim bill Before I explain the science behind the 34 precisely placed holes Let me do a little ad for another video. I did a little mini sled as well as this big sled bigger sled It's not real big purposely. I designed it to be light so there's little mini sled it's just for a little bitty cuts and for little angular things and Just something that's light and I can grab off the wall and slap on the table saw with little or no effort and It can use these Match fit clamps in order to hold a little stop block the fence and then it can secure pieces With the match fit so take a look at that video. I'll put that link up there Wherever there is somewhere just look for it. It'll be here or there All right now we get to This sled which is all finished. I put a protective guard on the back Which is nothing more than three pieces of Actually six pieces of three-quarter inch plywood being overly safe And they're just glued on there and then there's a channel cut in those for the blade And I've marked these off to say hey don't put your hands there Because I can hold my work pieces down with the match fit clamp I don't have to put my hands in here and hold down a piece So I can just slide this in and hold down a piece Okay, finally what you've been waiting for What is the Rationale of the 34 holes there are three-quarter inch holes I have a neighbor who's a retired Aerospace engineer spent his entire career with NASA and His team and his job and he was the head of that team was to cut down on the friction On the space capsule during re-entry so that it wouldn't overheat and destroy itself And in his scholarly research for how to do that he ran across an epistle by some Finch way Tai Chi Masters of the 11th century and they described in an artifact that he found a Precisely out of the holes that if put into a surface Would result in the hyperbole of the air resistance folding over on itself and creating a dissonant Compaction of the air that would make this surface slide without friction and more smoothly And so I decided to give it a try Now I know you guys and girls are a skeptical bunch So I'm going to demonstrate The effect of having these 34 holes in this pattern on this cross-cut slit I put a piece of walnut in here I've got it held down with a match fit clamp So there'd be no Tom Fulery. You won't see me move anything and I've got a stop block So we're all ready to go. Let's do the cut and I'll show you how fast It works. Hey, you want to see that again? What? You don't think it cut? Ha ha ha Now if you believe that I've got a Brooklyn bridge for sale And in reality the scrap wood that I grabbed in order to make this sled already had a couple holes in it In fact, it's had about six. I got rid of most of them when I cut off the the wings here in order to make this light I cut these down to make it as light as possible And I decided to drill all those holes because I already have some holes in it to see if that would also lighten it up I measured it I weighed it before the holes and after the holes and they made almost zero difference so I decided not to continue with that process because I didn't want to weaken the Integrity of the plywood so anyway, that's what they are originally for They are now just something to make it unique as compared to anybody else's When you do your woodworking you want to do things that are a little bit unique Not just a total copy of somebody else small workshop guy signing off